Replacement light assembly

ABSTRACT

A light assembly for a hand-held medical diagnostic instrument. The light assembly includes a substrate having a top surface and a bottom surface, a light source mounted to the top surface, and the bottom surface having first and second electrical terminals. The light assembly further includes a circuit board disposed inclined to the substrate, the circuit board having first and second electrical terminals, a first connector mounting and electrically connecting the first electrical terminal of the substrate to the first electrical terminal of the circuit board, a second connector mounting and electrically connecting the second electrical terminal of the substrate to the second electrical terminal of the circuit board, a heat sink, and a thermal conductor thermally connecting at least one of the first and second electrical terminals of the substrate to the heat sink.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation of pending U.S. patent applicationSer. No. 12/828,760, filed Jul. 1, 2010, the entire disclosure of whichis incorporated herein by reference.

STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT

Not applicable.

REFERENCE TO A “SEQUENCE LISTING”

Not applicable.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This disclosure generally relates to the field of illumination, and moreparticularly, to a replacement light assembly for hand-held medicaldiagnostic instruments, such as those used in physicians' offices,healthcare facilities, or other medical environments.

2. Description of Related Art

Many hand-held medical diagnostic instruments such as otoscopes,ophthalmoscopes, and the like utilize miniature incandescent lamps, suchas halogen or xenon lamps, as illumination sources. These lampstypically include a miniature filament, and are housed within the handleor the head of the instrument. The instruments may utilize one or morefiber optic bundles, lenses, mirrors, and/or other optical components totransmit light and/or other radiation from the lamp to an opening of thediagnostic instrument, thereby illuminating a medical target, such as aportion of the patient's anatomy, for examination.

Recently, however, there has been considerable interest in the field oflight emitting diodes (“LEDs”) as a potential substitute for suchincandescent lamps. Such LEDs typically provide better illuminationcapabilities than the incandescent lamps discussed above, and aretherefore desired for use in a variety of medical applications and otherapplications. Such LEDs also typically exhibit longer life, greaterresistance to shock and/or impact, cooler operating temperatures, andother more desirable operating characteristics than miniatureincandescent lamps. Moreover, some LEDs, such as color LEDs, may provideadditional benefits over incandescent lamps such as spectral tuning,spectrally-specific illumination, and the like.

Accordingly, it may be desirable to replace the incandescent bulbsutilized in an existing hand-held diagnostic instrument with LEDs asillumination sources. There are, however, a number of significantoptical, mechanical, thermal, and/or other differences between LEDs andincandescent lamps which must be considered when replacing such lampswith LEDs in known medical diagnostic instruments. For example,incandescent lamps are typically larger than LEDs, and emit light andother radiation having different optical characteristics than lightemitted by LEDs. Thus, there is a need to develop a replacement lightassembly which can be mechanically, optically, and electricallyincorporated into, for example, existing hand-held medical diagnosticinstruments without making mechanical, optical, and/or othermodifications to these diagnostic instruments.

Embodiments of the present disclosure satisfy the needs noted above.

BRIEF SUMMARY OF THE INVENTION

In an exemplary embodiment of the present disclosure, a light assemblyfor a hand-held medical diagnostic instrument includes a substratehaving a top surface and a bottom surface, a light source mounted to thetop surface, and the bottom surface having first and second electricalterminals. The assembly also includes a circuit board disposed inclinedto the substrate, the circuit board having first and second electricalterminals, a first connector mounting and electrically connecting thefirst electrical terminal of the substrate to the first electricalterminal of the circuit board, and a second connector mounting andelectrically connecting the second electrical terminal of the substrateto the second electrical terminal of the circuit board. The assemblyfurther includes a heat sink, and a conductor thermally connecting atleast one of the first and second electrical terminals of the substrateto the heat sink.

In such an exemplary embodiment, the thermal conductor thermallyconnects the at least one electrical terminal to the heat sink via oneof the first and second connectors, the thermal conductor includes anelectrically insulative material, and the thermal conductor includes anepoxy substantially overlaying the circuit board and the first andsecond connectors. In another exemplary embodiment, the thermalconductor thermally connects the circuit board to the heat sink, and theheat sink includes a thermally conductive housing extending about thecircuit board. The housing defines a chamber, and the thermal conductorsubstantially fills the chamber around the circuit board. In anotherexemplary embodiment, the heat sink includes a housing defining alongitudinal axis and a shoulder substantially perpendicular to thelongitudinal axis. In such an exemplary embodiment, the assembly furtherincludes a lens overlaying the light source, the lens contacting theshoulder and directing radiation from the light source to a target. Thelens is fixed relative to the light source such that contact between theshoulder and the lens disposes the light source at a desired positionalong the longitudinal axis.

In another exemplary embodiment, the heat sink includes a housingdefining a longitudinal axis and a keyway extending substantiallyparallel to the longitudinal axis. In such an exemplary embodiment, alens is fixed relative to the light source and defines a key disposedwithin the keyway. The key fixes the light source at a desired radialposition about the longitudinal axis. In addition, the housing includesa cylindrical outer wall, and a pin disposed on the outer wall coplanarwith the longitudinal axis and the keyway. In such an exemplaryembodiment, the pin is formed by the outer wall.

In another exemplary embodiment, the assembly further includes a lensfixed relative to the light source. The lens includes a concave surfacereceiving a radiation from the light source and one of a planar and aconvex surface directing the received radiation toward a target. In suchan exemplary embodiment, the planar surface is disposed at an anglerelative to the substrate.

In still another exemplary embodiment, the assembly further includes alens fixed relative to the light source. The lens includes a planarsurface receiving radiation from the light source, and one of a planarsurface and a convex surface directing the received radiation toward thetarget. In such an exemplary embodiment, the planar surface is disposedat an angle relative to the substrate. In still a further exemplaryembodiment, the assembly further includes a lens fixed relative to thelight source. The lens includes a saddle-shaped surface receivingradiation from the light source and a planar surface directing thereceived radiation toward a target. In such an exemplary embodiment, theplanar surface is disposed at an angle relative to the substrate. Instill another exemplary embodiment, the assembly further includes a lensdefining a first surface receiving radiation from the light source, asecond surface directing the received radiation toward a target, and amounting surface fixed to the substrate.

In another exemplary embodiment of the present disclosure, a method ofmanufacturing a light assembly for a hand-held medical diagnosticinstrument includes providing an LED mounted to a substrate, thesubstrate having a pair of electrical terminals. The method furtherincludes mounting and electrically connecting the electrical terminalsof the substrate to corresponding electrical terminals of a circuitboard of the light assembly, and thermally connecting the electricalterminals of the substrate to a heat sink of the light assembly.

In such an exemplary embodiment, the method further includeselectrically insulating the electrical terminals of the substrate fromthe heat sink. The method also includes overlaying the electricalterminals of the substrate, the heat sink, and a portion of the circuitboard with an electrically insulative thermal conductor. Such anexemplary method also includes connecting a lens to the substrate, aportion of the lens being supported by the heat sink. In such anexemplary embodiment, the heat sink includes a cylindrical housinghaving an open end, and the method also includes connecting an alignmentpin to an outer wall of the housing at a predetermined distance from theopen end. The method also includes mounting the substrate within thepinned housing.

In still a further exemplary embodiment of the present disclosure, alight assembly for a hand-held medical diagnostic instrument includes athermally conductive cylindrical housing defining an open end, a lensdisposed proximate the open end, and an LED mounted to a substrate andfixed relative to the lens, the substrate defining a pair of electricalterminals. In such an exemplary embodiment, the light assembly alsoincludes a light assembly circuit board disposed within the housing, theelectrical terminal is mounted and electrically connected to the circuitboard. The light assembly further includes an electrically insulativethermal conductor thermally connecting the electrical terminals to thehousing.

In a further exemplary embodiment of the present disclosure, a method offorming a lens for a hand-held medical diagnostic instrument includesproviding a mold body having a first end, a second end, and a cavitybetween the first and second ends, the cavity configured to receive aflow of lens material. Such an exemplary method further includesconnecting a first insert to the first end such that an optical surfaceof the first insert is fluidly connected to the cavity, the opticalsurface of the first insert being one of planar and concave. The methodalso includes connecting a second insert to the second end such that anoptical surface of the second insert is fluidly connected to the cavity,the optical surface of the second insert being one of planar, concave,and saddle shape. The method further includes filling the cavity withthe flow of lens material to form a lens, the optical surfaces of thefirst and second inserts forming corresponding optical surfaces on thelens.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

FIG. 1 is a partial side cross-sectional view of a head of an exemplaryhand-held medical diagnostic instrument.

FIG. 2 is a partial side cross-sectional view of the instrument of FIG.1.

FIG. 3 illustrates a lens mold and a plurality of inserts according toan exemplary embodiment of the present disclosure.

FIG. 4 is a cross-sectional view of a lens according to an exemplaryembodiment of the present disclosure.

FIG. 5 is a cross-sectional view of a lens according to anotherexemplary embodiment of the present disclosure.

FIG. 6 is a cross-sectional view of a lens according to still anotherexemplary embodiment of the present disclosure.

FIG. 7 is a cross-sectional view of a lens according to a furtherexemplary embodiment of the present disclosure.

FIG. 8 is a cross-sectional view of a replacement light assemblyaccording to an exemplary embodiment of the present disclosure.

FIG. 9 is an enlarged view of a portion of the assembly illustrated inFIG. 8.

FIG. 10 is another cross-sectional view of the assembly shown in FIG. 8.

FIG. 11 is an enlarged view of a portion of the assembly shown in FIG.10.

FIG. 12 is an isometric view of a light source and a substrate accordingto an exemplary embodiment of the present disclosure.

DETAILED DESCRIPTION OF THE INVENTION

FIGS. 1 and 2 illustrate a hand-held medical diagnostic instrument 10according to an exemplary embodiment of the present disclosure.Embodiments of the present disclosure may be utilized with any of avariety of hand-held medical diagnostic instruments such as, forexample, ophthalmoscopes, otoscopes, vaginascopes, and the like. Forease of description, however, an exemplary otoscope shall be describedfor the duration of this disclosure unless otherwise noted.

As shown in FIGS. 1 and 2, the medical diagnostic instrument 10 mayinclude an instrument head 18 attached to the top of a handle 14. Thehandle 14 and/or the instrument head 18 may be substantially hollow, andthe instrument head 18 may include a frustoconical tip portion 40 ontowhich a disposable speculum (not shown) may be fitted in a conventionalmanner. In an exemplary embodiment, the speculum may be sized, shaped,and/or otherwise configured to fit a predetermined distance into an earcanal of a patient so that, for example, the tympanic membrane or othermedical target may be examined. The tip portion 40 may have an opening42 at the distal end thereof, and an eye piece 46 may be attached to theproximal end 48 of the instrument head 18 to assist in such examination.Accordingly, in an exemplary embodiment, the eye piece 46 may form partof an optical path with the opening 42 through the hollow instrumenthead 18 to permit viewing of a medical target. While the tympanicmembrane may be one such target, it is understood that other exemplarymedical diagnostic instruments 10 may be utilized to view other likemembranes or targets. Such exemplary medical targets may includeportions of the eye, nose, throat, and/or other portions of the humananatomy.

Exemplary medical diagnostic instruments 10 may employ, for example, anincandescent lamp 22, such as, for example, a halogen or xenon lamp. Atleast a portion of such an incandescent lamp 22 may be mounted to,retained within, and/or otherwise associated with a housing 25 disposedwithin a base 27 or other portion of the instrument head 18. Theincandescent lamp 22 may be functionally, electrically, and/or otherwiseoperably connected to a power supply within the medical diagnosticinstrument 10 or to an external power supply. For example, theincandescent lamp 22 may be electrically connected to one or morebatteries 26 retained in a compartment of the instrument handle 14.Alternatively, the instrument handle 14 and/or other portions of themedical diagnostic instrument 10 may be electrically connected to aconventional wall outlet or other similar power supply via an electricalcord (not shown) or other like connection. It is also understood thatthe medical diagnostic instrument 10 may employ one or more springs 33,pins 31, controls 30, and/or other components to assist in maintainingan effective electrical connection between the incandescent lamp 22 andthe power supplies discussed above. Such components may also assist incontrolling, for example, the current and/or voltage supplied to theincandescent lamp 22.

In an exemplary embodiment in which the medical diagnostic instrument 10comprises an otoscope, the instrument 10 may also include a bundle ofoptical fibers 38 extending from proximate the incandescent lamp 22,through the base 27 of the instrument head 18, to a bundle of lighttransmitting ends 36 or other optical means that are disposed at thedistal opening 42. The optical fibers 38 and the transmitting ends 36may be configured to illuminate the medical target during examination.

Alternatively, in an exemplary embodiment in which the medicaldiagnostic instrument 10 comprises an ophthalmoscope, the bundle ofoptical fibers 38 may be omitted. Instead, in such an exemplaryembodiment, the medical diagnostic instrument 10 may further compriseone or more collimating lenses, reticles, positive lenses, negativelenses, mirrors, and/or other optical or beam shaping components todirect radiation emitted by the incandescent lamp 22. For example, anexemplary ophthalmoscope may include a mirror that is offset from, forexample, a central or optical axis of the incandescent lamp 22. Such amirror may be configured to direct radiation emitted by the incandescentlamp 22 in the direction of the medical target optically downstream of,for example, a reticle of the ophthalmoscope. Such mirror positioningmay be required due to, for example, the configuration of theophthalmoscope head 18. To compensate for such off-axis or offset mirrorpositioning, the exemplary ophthalmoscope may further employ one or moreprisms, wedges, and/or angled optical components optically downstream ofthe incandescent lamp 22 to direct light and/or other radiation emittedby the incandescent lamp 22 in the direction of the offset mirror.

In still another exemplary embodiment in which the medical diagnosticinstrument 10 comprises an ophthalmoscope, the offset mirror describedabove may, instead, be substantially aligned with, for example, thecentral or optical axis of the incandescent lamp 22. In such anexemplary embodiment, one or more of the optical components describedabove for shifting and/or angling light emitted by the incandescent lamp22 in the direction of the mirror may not be required.

FIGS. 8 through 11 illustrate an exemplary light assembly 8 of thepresent disclosure in which the incandescent lamp 22 has been replacedby a different light source such as, for example, an LED. Such anexemplary light source 12 is illustrated in greater detail in FIG. 12,and the light source 12 may comprise an LED, a low-intensity laser,and/or any other light source known in the art. For ease of description,however, an exemplary embodiment in which the light source 12 comprisesan LED shall be described for the duration of this disclosure unlessotherwise noted.

The incandescent lamp 22 discussed above can be replaced with one ormore LEDs to illuminate a medical target during examination. Replacingan incandescent lamp 22 with an LED in this way may improve, forexample, the durability, illumination, and/or other qualities of theinstrument 10, and thus may be desirable in modern hand-held medicaldiagnostic instruments 10. In replacing an incandescent lamp 22 with anLED, one or more lenses or other additional optical components may beemployed to shape the light emitted by the LED. Such components maybend, shift, collimate, focus, and/or otherwise shape the radiationemitted by the LED to substantially match the optical characteristics ofthe incandescent lamp 22 such that the functionality of the medicaldiagnostic instrument 10 may remain substantially unchanged.

In an exemplary embodiment, the light assembly 8 may include a lightsource 12 mounted to a substrate 16, and a circuit board 44 disposedinclined to the substrate 16. The assembly 8 may also include first andsecond connectors 54 mounting and electrically connecting the circuitboard 44 to the substrate 16. Such an exemplary light assembly 8 mayfurther include one or more heat sinks, and a thermal conductor 56thermally connecting at least one of the heat sinks to the substrate 16.

In an exemplary embodiment, the substrate 16 may be constructed fromplastics, polymers, and/or other typical circuit board material, and maycomprise a printed circuit board. For example, the substrate 16 mayinclude one or more electrical terminals embedded therein and/orotherwise formed thereon. Exemplary electrical terminals 32, 34 may bepositive and negative electrical terminals, respectively. Suchelectrical terminals 32, 34 may be electrically and/or otherwiseoperably connected to one or more components disposed on the substrate16. For example, the electrical terminals 32, 34 may be configured toprovide and/or otherwise direct an electrical current and/or voltagefrom a power source, such as the batteries 26 of the medical diagnosticinstrument 10, to the light source 12 mounted on the substrate 16. Asshown in at least FIGS. 9 and 11, the substrate 16 may have a topsurface 20 and a bottom surface 24. In an exemplary embodiment, thelight source 12 may be disposed on and/or otherwise mounted to the topsurface 20, and the bottom surface 24 may define and/or otherwiseinclude the electrical terminals 32, 34 discussed above.

As shown in greater detail in FIG. 12, a cover 28 may be mounted onand/or otherwise connected to the substrate 16. The cover 28 may be, forexample, substantially transparent to permit light and/or otherradiation emitted by the light source 12 to pass through the cover 28 toa lens 62 of the light assembly 8. The cover 28 may have any shape,size, and/or other configuration known in the art. For example, thecover 28 may be substantially convex, and may act as a positive lens. Insuch an exemplary embodiment, the cover 28 may assist in collectingand/or otherwise focusing divergent light emitted by the light source12. Alternatively, the cover 28 may be substantially planar, therebyproviding substantially no added intensification of the emitted light.In still another exemplary embodiment, at least a portion of the cover28 may be substantially concave, and may act as a negative lens. In suchan embodiment, the concave portion of the cover 28 may act as a negativelens and may assist in further diverging the light emitted by the lightsource 12. The light emitted by the light source 12 may pass through anair gap 29 between the cover 28 and the lens 62 before reaching the lens62.

The lens 62 may have any shape, size, and/or other configuration knownin the art to assist in bending, shifting, angling, shaping, focusingcollimating, and/or diverging the light emitted by the light source 12optically upstream of the other optical components of the medicaldiagnostic instrument 10. For example, the lens 62 may be shaped, sized,and/or otherwise configured to modify the path, orientation, intensity,and/or other optical characteristics of the light emitted by the lightsource 12 to substantially match the corresponding opticalcharacteristics of the radiation emitted by an incandescent lamp 22previously employed by the medical diagnostic instrument 10. Thus, thecombination of the lens 62 and light source 12 may be utilized as adirect replacement for incandescent lamps 22 commonly used in otoscopes,ophthalmoscopes, vaginascopes, and other known hand-held medicaldiagnostic instruments 10. Due to the configurations of the light source10 and the lens 62, these components may replace such incandescent lamps22 without further modifications to, for example, the light assembly 8or other hand-held medical diagnostic instrument components.

The lens 62 may be fixed relative to the light source 12 in order tomaintain the desired beam-shaping effect on the light emitted by thelight source 12. In an exemplary embodiment, the lens 62 may be mountedon and/or otherwise connected to the substrate 16 by any known means.For example, an adhesive 15 may be disposed between, for example, one ormore mounting surfaces 84 of the lens 62 and the top surface 20 of thesubstrate 16. Alternatively, at least a portion of the lens 62 may bemolded onto the substrate 16. In still a further exemplary embodiment,the lens 62 may define one or more grooves, clips, slots, notches,shoulders, and/or other known retention components to assist in fixedlydisposing the substrate 16 relative to the lens 62.

As shown in FIGS. 3-7, the lens 62 may have any number of configurationsin order to desirably shape a beam or other radiation emitted by thelight source 12. For example, the shape, size, and/or otherconfigurations of the lens 62 may be designed to desirably shape thelight emitted by the light source 12 to match one or more differentfilament configurations of an incandescent lamp 22 previously utilizedin known hand-held medical diagnostic instruments 10. Such lenses 62 maybe formed by any known lens-formation process including, for example,casting, molding, and/or other processes. For example, the lenses 62 ofthe present disclosure may be formed through a known blown or injectionmolding process in which a universal mold 86 is utilized to form lenses62 having a variety of different configurations. As shown in FIG. 3, aplurality of different inserts may be utilized in conjunction with themold 86 to form lenses 62 having different configurations and, thus,different optical characteristics. As indicated in FIG. 3, any ofInserts A, B, C may be inserted into a first portion or end 83 of themold 86 while any of Inserts 1, 2, 3 may be inserted into a secondportion or end 85 of the mold 86. In still further exemplaryembodiments, the Inserts A, B, C, 1, 2, 3 may be interchangeable. Insuch embodiments, any of the Inserts may be inserted into and used inthe first end 83 and/or the second end 85 of the mold 86. A cavity 87 ofthe mold 86 between the first and second ends 83, 85 may then be filledwith a flow of lens material to form lenses 62 having variouscharacteristics. For example, optical surfaces 89 of the Inserts A, B,C, 1, 2, 3 may form corresponding optical surfaces on the resultinglenses 62. In an exemplary embodiment, the optical surfaces of thelenses 62 may be any of the concave surfaces 74, planar surfaces 76, 78,convex surfaces 80, saddle-shaped surfaces 82, or other lens surfacesdiscussed herein.

For example, in an embodiment in which the medical diagnostic instrument10 comprises an ophthalmoscope, magnification of the light emitted bythe light source 12 may not be required. In such an exemplaryembodiment, a lens 62 having a substantially planar top optical surface76 and a substantially concave light-receiving optical surface 74 may beutilized. In order to form such a lens 62, Insert 2 may be inserted intothe second end 85 of the mold 86 and Insert A may be inserted into thefirst end 83 of the mold 86. A lens 62 formed using Insert 2A isillustrated in FIG. 6.

In another exemplary ophthalmoscope embodiment, Insert 2 may be replacedwith Insert 1 in the second end 85 of the mold 86 to form a lens 62having a substantially planar light-receiving optical surface 78. Suchan exemplary lens 62 is shown in FIG. 7. The planar optical surface 78may provide substantially no magnification to the light emitted by thelight source 12, while the concave light-receiving optical surface 74may cause further diffraction of such light. Accordingly, the concavesurface 74 may act as a negative lens reducing the power and/orintensity of the light produced by the light source 12.

In additional exemplary ophthalmoscope embodiments, there may be a needto skew and/or otherwise direct light emitted by the light source 12 atan angle relative to, for example, an optical axis 90 (FIGS. 9 and 11)of the light source 12. In such exemplary embodiments, theophthalmoscope may employ one or more mirrors, lenses, and/or otheroptical components to receive such skewed and/or angled light, andredirect such light toward the medical target. In order to angle or skewthe light emitted by the light source 12, the planar optical surface 76of the lens 62 may be formed of any desirable angle relative to, forexample, the horizontal or to one or more mounting surfaces 84 definedby the lens 62. Such an exemplary lens 62 is shown in FIG. 5, wherebythe planar optical surface 76 is inclined relative to the mountingsurface 84. The lens 62 illustrated in FIG. 5 may correspond to a lensformed using Insert 2 disposed in the second end 85 of the mold 86, andthe Insert B disposed in the first end 83 of the mold 86 (FIG. 3). Infurther exemplary embodiments, either of Inserts 1 or 3 may besubstituted for Insert 2 in the second end 85 of the mold 86 to form alens 62 capable of angling or skewing emitted by the light source 12. Itis understood that utilizing Insert 1 may form a lens 62 having a planaroptical surface 78 having substantially no magnification effect on thelight received thereby, while light received by a substantiallysaddle-shaped optical surface 82 (shown as a dashed line in FIG. 3) of alens 62 formed by the Insert 3 may be spread, stretched, and/orotherwise dispersed in any desired direction depending on the opticalrequirements of the ophthalmoscope.

Alternatively, in an exemplary embodiment in which the medicaldiagnostic instrument 10 comprises an otoscope, as in FIGS. 1 and 2, thelens 62 may be sized, shaped, and/or otherwise configured to directlight emitted by the light source 12 onto optical fibers 38. In anexemplary embodiment, the lens 62 may be configured to focus the lightemitted by the light source 12 onto the fibers 38, thereby increasingthe intensity and/or power of the light. In such an exemplaryembodiment, the Insert 1 may be inserted into the second end 85 of themold 86 and the Insert C may be inserted into the first end 83 of themold 86. A lens 62 formed using such inserts is shown in FIG. 4. Asshown in FIG. 4, such a configuration may form a lens 62 having asubstantially planar optical surface 78 configured to receive the lightemitted by the light source 12, and a convex optical surface 80configured to focus the light passing therethrough.

One of ordinary skill in the art will appreciate that employing auniversal mold 86 and a variety of easily removable, insertable, andinterchangeable Inserts 1, 2, 3, A, B, C may assist in streamlining thelens formation process. In particular, using a universal mold 86 andInserts 1, 2, 3, A, B, C may reduce the amount of time required for lensformation and may require far less tooling than known injection or blownmolding processes, thereby reducing the expense involved in forminglenses 62 of the type described herein.

As shown in FIGS. 8 through 11, the lens 62 may be mounted on and/orotherwise supported by a shoulder 64 defined by the housing 25. In anexemplary embodiment, the shoulder 64 may be etched, milled, and/orotherwise formed in a sidewall or inner wall of the housing 25. Theshoulder 64 may be formed at a distance d from a distal end 88 of thehousing 25 so as to dispose the lens 62 and/or the light source 12connected to the lens 62 at a desired position relative to the housing25. For example, the size, shape, depth, position, and/or otherconfigurations of the shoulder 64 may assist in positioning the lens 62and/or the light source 12 at a desired position along a longitudinalaxis 60 of the housing 25. Such positioning of, for example, the lightsource 12 may streamline the assembly process of the light assembly 8and may also assist in standardizing the optical characteristics of theassembled light assembly 8 in a process in which the light assemblies 8are mass-produced. For example, in exemplary embodiments in which theinstrument 10 comprises an ophthalmoscope, the shoulder 64 may assist indisposing the light source 12 at a desired distance d from the distalend 88, thereby enabling the lens 62 to accurately and repeatably focuslight emitted by the light source 12 onto, for example, collimatinglenses, reticles, positive lenses, mirrors, and/or other opticalcomponents at a fixed position optically downstream of the light source12 within the instrument 10. In such an exemplary embodiment, disposing,for example, the light source 12 and/or the lens 62 accurately along thelongitudinal axis 60 may be required for optimal performance of theinstrument 10.

To further assist in positioning and/or aligning the lens 62 and/or thelight source 12 relative to the housing 25, the housing 25 may alsodefine one or more keyways 66 proximate the distal end 88. The keyway 66may be formed within a sidewall and/or inner wall of the housing 25through any of the processes discussed above with regard to the shoulder64. In an exemplary embodiment, the keyway 66 may be a channel extendingsubstantially parallel to the longitudinal axis 60 of the housing 25,and the keyway 66 may be configured to mate with and/or otherwise accepta corresponding key 68 of the lens 62. In an exemplary embodiment, thekey 68 may be inserted into the keyway 66 for radial alignment of thelens 62 and/or the light source 12 about the longitudinal axis 60 of thehousing 25.

Such radial alignment of the light source 12 and/or lens 62 clockwise orcounter-clockwise about the axis 60 may be useful in exemplaryembodiments in which the instrument 10 comprises an ophthalmoscope orother instrument comprising optical components configured to acceptstretched, flattened, shifted, angled, and/or otherwise modified beamsof light from the light source 12. Such optical components may beconfigured to receive modified light beams from various filamentsemployed by incandescent lamps 22. Accordingly, aligning the lens 62and/or light source 12 utilizing, for example, the keyway 66 and key 68arrangement described above may assist in easily replacing such lamps 22while satisfying the optical requirements of the particular instrument10.

To further assist in desirably aligning the light source 12, lens 62,and/or housing 25, the housing 25 may be equipped with one or more pins72 disposed on an outer wall 70 of the housing 25. In an exemplaryembodiment, the pin 72 may be made from substantially the same materialas the housing 25, and the pin 72 may be spot welded, press fit,adhered, and/or otherwise connected to the housing 25. Alternatively,the pin 72 may be milled and/or otherwise machined from the outer wall70 of the housing 25 such that the housing 25 and the pin 72 are formedfrom the same piece of material. The pin 72 may be disposed at adistance D from the distal end 88 of the housing 25 in order to assistin positioning the light assembly 8 at a desired depth or locationwithin the base 27 of the instrument 10. For example, the base 27 maydefine one or more channels (not shown) configured to accept the pin 72,and such channels may be configured to position the light assembly 8 ata desired depth or longitudinal location within the base 27. Such alongitudinal location may dispose, for example, the light source 12 adesired depth or longitudinal distance away from one or more opticalcomponents of the instrument 10. In addition, the pin 72 may be alignedwith the keyway 66, key 68, and/or the light source 12. In an exemplaryembodiment, the pin 72 may be disposed on the outer wall 70 coplanarwith the longitudinal axis 60 of the housing 25 and the keyway 66.Aligning the pin 72 in this way may assist in radially aligning, forexample, the light source 12, lens 62, and/or housing 25 relative to thebase 27 and/or to the downstream optical components of the instrument10. As described above, such radial alignment may assist in satisfyingthe optical requirements of such optical components, and may facilitateeasy replacement of an incandescent lamp 22 with the light assembly 8 ofthe present disclosure.

In addition, the location and/or other configurations of the keyway 66may enable the pin 72 to be connected to and/or formed on the housing 25prior to mounting, for example, the lens 62 and/or the light source 12within the housing 25. Disposing the pin 72 at a distance D from thedistal end 88, and coplanar with the axis 60 and the keyway 66 mayeliminate the need for optical alignment of the light source 12 and/orlens 62 relative to the housing 25, and may also eliminate the need forseparate pinning of the housing 25 after such optical alignment iscompleted. Eliminating these steps may simplify assembly, and reduce thecost and time required for manufacturing the light assembly 8.

As shown in FIGS. 8 through 11, the light assembly 8 may further includea circuit board 44 defining one or more terminals 50, 52. In anexemplary embodiment, the circuit board 44 may be a conventional printedcircuit board including one or more drive, voltage control, currentcontrol, and/or other control components of the light assembly 8. Thecircuit board 44 may be any shape, size, and/or other configuration topermit convenient disposal and/or mounting within, for example, achamber 58 of the housing 25. For example, the circuit board 44 may besubstantially rectangular in shape, and may have a width less than awidth and/or diameter of the chamber 58. The circuit board 44 may alsohave a length less than a length of the chamber 58 to facilitatedisposal of the circuit board 44 within the chamber 58.

In an exemplary embodiment, the circuit board 44 may extendsubstantially parallel to an optical axis 90 of the light source 12. Theoptical axis 90 may be parallel to and/or collinear with thelongitudinal axis 60 of the housing 25. Alternatively, the optical axis90 may be parallel to and offset from the axis 60. Although FIG. 9illustrates the circuit board 44 being disposed substantially parallelto the optical axis 90, in additional exemplary embodiments, the circuitboard 44 may be disposed at any desired angle relative to the opticalaxis 90 to facilitate connecting the circuit board 44 to the substrate16 and/or mounting the circuit board 44 within the chamber 58.

The circuit board 44 may be mechanically and/or electrically connectedto the substrate 16 in any conventional way. For example, one or moreclips, pins, teeth, grooves, and/or other known connection devices maybe employed to facilitate a mechanical connection between the substrate16 and the circuit board 44. Likewise, one or more leads, wires, solderbeads, and/or other electrical connectors may be employed to form one ormore electrical connections between the substrate 16 and the circuitboard 44, and/or between components of the substrate 16 and respectivecomponents of the circuit board 44. In an exemplary embodiment, at leastone of the connection devices discussed above may form both a mechanicalconnection and an electrical connection between the substrate 16 and thecircuit board 44, and/or between respective components of the substrate16 and the circuit board 44.

For example, as illustrated in FIGS. 8 and 9, one or more connectors 54may be disposed between the substrate 16 and the circuit board 44 toform both an electrical connection and a mechanical connectiontherebetween. In an exemplary embodiment, the connectors 54 may compriseone or more beads of solder mounting and electrically connecting atleast a portion of the substrate 16 to a corresponding portion of thecircuit board 44. In an exemplary embodiment, the connectors 54 maymount and electrically connect the first terminal 32 of the substrate 16to the first terminal 50 of the circuit board 44. In such an exemplaryembodiment, a second connector 54 may also mount and electricallyconnect the second terminal 34 of the substrate 16 to the secondterminal 52 of the circuit board 44. In such an exemplary embodiment,the connectors 54 may extend along at least a portion of the width ofthe circuit board 44. Alternatively, the connectors 54 may be disposedsubstantially locally, so as to form isolated areas of connectionbetween corresponding terminals of the substrate 15 and circuit board44. Accordingly, the size, location, and/or other configurations of theconnectors 54 may substantially correspond to the correspondingconfigurations of the terminals 32, 34, 50, 52 described above.

In addition to mounting and/or electrically connecting the substrate 16to the circuit board 44, the substrate 16 may also be thermallyconnected to the circuit board 44. In an exemplary embodiment, theelectrical terminals 32, 34 of the substrate 16 may be thermallyconnected to the corresponding electrical terminals 50, 52 of thecircuit board 44 during assembly, and such a thermal connection may beformed by, for example, one or more of the connectors 54 discussedabove. For example, one or more of the connectors 54 may form anelectrical, mechanical, and thermal connection between the substrate 16and the circuit board 44 at the respective terminals thereof. Such athermal connection may be useful in removing and/or dissipating heatfrom portions of the substrate 16 and/or portions of the circuit board44.

For example, the connectors 54 may be employed to remove heat from theterminals 32, 34 of the substrate 16 and/or the terminals 50, 52 of thecircuit board 44 by thermally connecting the connectors 54 to one ormore active or passive cooling devices. Such cooling devices may bedisposed within, for example, the chamber 58. Alternatively, suchdevices may be disposed external to the housing 25.

In still another exemplary embodiment, such cooling devices may beincorporated into the circuit board 44, housing 25, and/or othercomponents of the light assembly 8 or the instrument 10. For example,such cooling devices may comprise one or more heat sinks mounted to thecircuit board 44, housing 25, base 27, handle 14, or other components ofthe instrument 10. In still another exemplary embodiment, one or morecomponents of the instrument 10 or the light assembly 8 may comprise aheat sink configured to draw and/or otherwise dissipate heat from thesubstrate 16 and/or the circuit board 44. For example, the housing 25may comprise one or more fins or other passive cooling devicesconfigured to assist in dissipating heat from the substrate 16 and/orthe circuit board 44. In still a further exemplary embodiment, thehousing 25 may comprise a heat sink, and at least a portion of thehousing 25 may be thermally connected to at least one of the terminals32, 34 of the substrate 16 and/or the terminals 50, 52 of the circuitboard 44 to remove heat therefrom.

In an exemplary embodiment, a thermal connection may be formed betweenthe terminals 32, 34, 50, 52 and the housing 25 via one or more of theconnectors 54 discussed above. Such a thermal connection may be formedby any thermally conductive material or structure known in the artdisposed between the terminals 32, 34, 50, 52 and the housing 25. Forexample, as shown in FIGS. 8 through 11, a thermal conductor 56 may bedisposed within the chamber 58 thermally connecting at least one of theterminals 32, 34, 50, 52 to the housing 25 and/or any other heat sink ofthe light assembly 8. Such a thermal connection may be formed betweenthe terminals and the heat sink via at least one of the connectors 54.The thermal conductor 56 may comprise an electrically insulativematerial such that the thermal conductor 56 may come in contact with oneor more electrically conductive components of the light assembly 8without causing the light assembly 8 to short-circuit. In addition, anelectrically insulative thermal conductor 56 may be utilized to overlayportions of the substrate 16, circuit board 44, and/or componentsthereof, without causing damage to the light assembly 8.

In an exemplary embodiment, the thermal conductor 56 may comprise athermally conductive epoxy overlaying at least a portion of the circuitboard 44, as well as the connectors 54. Accordingly, the thermalconductor 56 may thermally connect the circuit board 44, substrate 16,terminals 32, 34, 50, 52, and/or connectors 54 to the housing 25 and/orone or more of the heat sinks discussed above.

As shown in FIGS. 8 through 10, the thermal conductor 56 maysubstantially fill at least a portion of the chamber 58 around thecircuit board 44. In such an exemplary embodiment, the circuit board 44and/or the substrate 16 may be substantially submerged within thethermal conductor 56. The thermal conductor 56 may remain substantiallygelatinous or may be configured to stiffen and/or harden, therebyassisting in supporting the circuit board 44 and/or the substrate 16within the chamber 58. In an exemplary embodiment, the thermal conductor56 may adhere to, bond with, and/or otherwise remain substantially fixedto the housing 25, circuit board 44, and/or substrate 16 to assist insecuring the substrate 16 and/or the circuit board 44 relative to, forexample, the housing 25.

In an exemplary embodiment, the housing 25 may be mechanically and/orthermally connected to the base 27 and/or the head 18. In addition, thebase 27 and/or the head 18 may be mechanically and/or thermallyconnected to the handle 14 of the instrument 10. In such exemplaryembodiments, each of these thermal connections may further assist indrawing heat from and/or dissipating heat from, for example, theterminals 32, 34, 50, 52.

In such an exemplary embodiment, each of the housing 25, base 27, head18, and handle 14 may act as a heat sink assisting in passively coolingthe terminals 32, 34, 50, 52. It is understood that by cooling one ormore of the terminals described above, one or more components connectedto the substrate 16 and/or the circuit board 44 may also be cooled. Forexample, dissipating heat from the terminals 32, 34 of the substrate 16may assist in cooling the light source 12 disposed on the substrate 16.In an exemplary embodiment in which the light source 12 comprises anLED, such cooling may be useful in maintaining a satisfactory LEDoperating temperature. For example, embodiments of such LEDs may have anoptimal operating temperature above which the efficiency, durability,and/or other operating characteristics of the LED may decrease toundesirable levels. Operating the LED above such temperatures may alsocause damage to the LED.

In an exemplary embodiment, the junction temperature (a temperaturemeasured at the junction between the LED and the substrate 16) may bemonitored and/or regulated using one of the heat sinks or other coolingdevices discussed above. Exemplary LEDs of the present disclosure mayhave a maximum junction temperature of approximately 85° C. In such anexemplary embodiment, the heat sinks, thermal conductor 56, connectors54, and/or other components of the present disclosure may assist inmaintaining the aforementioned junction temperature below approximately85° C. by assisting in dissipating and/or drawing heat from theterminals 32, 34 of the substrate 16. It is also understood thatadditional passes and/or active cooling devices may be utilized withlight assemblies 8 of the present disclosure in order to maintain and/orotherwise regulate the junction temperature or other thermal operatingrequirements of the light sources 12 discussed herein.

The invention has been described in detail with particular reference toa presently preferred embodiment, but it will be understood thatvariations and modifications can be effected within the spirit and scopeof the invention. The presently disclosed embodiments are thereforeconsidered in all respects to be illustrative and not restrictive. Thescope of the invention is indicated by the appended claims, and allchanges that come within the meaning and range of equivalents thereofare intended to be embraced therein.

The invention claimed is:
 1. A light assembly for a handheld medicalinstrument, comprising: a thermally conductive housing defining an openend; a substrate disposed proximate the open end, the substrate having atop surface and a bottom surface opposite the top surface; a lightsource mounted to the top surface of the substrate; an electricalterminal disposed on the bottom surface of the substrate, wherein thehousing is thermally connected to the terminal to remove heat from thesubstrate via the terminal; and an electrically insulative materialcontacting the bottom surface of the substrate and extending in thedirection of a longitudinal axis of the housing, the housing extendingabout the electrically insulative material.
 2. The light assembly ofclaim 1, wherein the housing comprises a heat sink configured to removeheat from the substrate.
 3. The light assembly of claim 1, wherein thehousing comprises a fin configured to remove heat from the substrate. 4.The light assembly of claim 1, further comprising a thermal conductorthermally connecting the terminal to the housing.
 5. The light assemblyof claim 1, further comprising a connector electrically connected to thesubstrate and configured to direct an electrical current to the lightsource.
 6. The light source of claim 5, wherein the electricallyinsulative material overlays the connector.
 7. The light source of claim5, wherein the terminal comprises a first electrical terminal of thesubstrate and the substrate further comprises a second electricalterminal, the housing being thermally connected to the first electricalterminal and the connector being electrically connected to the secondelectrical terminal.
 8. The light source of claim 1, wherein the housingincludes a shoulder configured to dispose the light source at a desiredposition relative to the housing.
 9. The light source of claim 1,wherein the longitudinal axis extends parallel to an optical axis of thelight source.
 10. The light assembly of claim 1, wherein theelectrically insulative material is disposed adjacent to a shoulder ofthe housing and the substrate within a central chamber of the housing,the longitudinal axis extending substantially centrally through thecentral chamber.
 11. The light assembly of claim 10, further comprisinga lens, the lens including a first surface receiving radiation from thelight source, a second surface directing the received radiation toward atarget, and a mounting surface fixed to the substrate.
 12. A lightassembly for a handheld medical instrument, comprising: a housingdefining a chamber, a central longitudinal axis, and an open end; asubstrate disposed proximate the open end, the substrate having a topsurface and a bottom surface opposite the top surface; an LED mounted tothe top surface of the substrate; a lens fixed relative to the LED andconfigured to shape light emitted by the LED; an electrically insulativematerial contacting the bottom surface of the substrate and extending inthe direction of the longitudinal axis, the housing extending about theelectrically insulative material; and an electrical terminal disposed onthe bottom surface of the substrate, wherein the housing is thermallyconnected to the terminal to remove heat from the substrate via theterminal.
 13. The light assembly of claim 12, wherein the lens isconnected to the top surface of the substrate.
 14. The light assembly ofclaim 12, wherein at least a portion of the lens is molded onto thesubstrate.
 15. The light assembly of claim 12, wherein the lens definesa retention component configured to assist in fixedly disposing thesubstrate relative to the lens.
 16. The light assembly of claim 12,wherein the lens comprises a concave light-receiving optical surface.17. The light assembly of claim 12, wherein the lens comprises a firstlens disposed along an optical axis of the LED, the light assemblyfurther comprising a second lens disposed along the optical axis. 18.The light assembly of claim 17, wherein the first lens is disposedoptically upstream of the second lens, and the second lens comprises aconvex optical surface configured to direct light emitted by the LED.19. The light assembly of claim 17, wherein the housing includes ashoulder configured to dispose the LED and the second lens at desiredrespective positions relative to the housing.
 20. A light assembly for ahandheld medical instrument, comprising: a housing including an internalchamber, an open end, a central longitudinal axis, and a plurality offins; a substrate disposed proximate the open end, the substrate havinga top surface and a bottom surface opposite the top surface; an LEDmounted to the top surface of the substrate; a first lens connected tothe top surface of the substrate; a second lens disposed opticallydownstream of the first lens, the first and second lenses being fixedalong an optical axis of the LED and configured to shape light emittedby the LED; an electrically insulative material contacting the bottomsurface of the substrate and extending in the direction of thelongitudinal axis, the housing extending about the electricallyinsulative material; and an electrical terminal disposed on the bottomsurface of the substrate and thermally connected to the housing, theplurality of fins configured to assist in removing heat from thesubstrate via the electrical terminal.
 21. The light assembly of claim20, wherein the housing includes a shoulder configured to dispose theLED and the second lens at desired respective positions relative to thehousing.
 22. The light assembly of claim 21, wherein the terminalcomprises a first electrical terminal of the substrate and the substratefurther comprises a second electrical terminal, the housing beingthermally connected to the first electrical terminal and a connectorconfigured to direct an electrical current to the LED being electricallyconnected to the second electrical terminal.
 23. The light assembly ofclaim 22, wherein the first lens comprises a concave light receivingoptical surface, and the second lens comprises a convex optical surfaceconfigured to direct light emitted by the LED.